Placement stability has been viewed as critical for the success of out-of-home care. Foster children who experience multiple placement changes place great demands on the service system. They consistently display higher levels of emotional and behavioral disturbance, and frequently require the most intensive and expensive forms of care. Little is known about the services provided to the foster child following the disruptive event of a placement change. An explicit assumption of this study is that a rational system of service delivery would at least respond to, if not prevent, such an event by providing increased therapeutic services--especially if the placement change is caused by problems in the child's psychosocial functioning, which is the most consistent predictor of placement change. The overall objective of this study is to investigate the relationship between placement change that is the result of problems in child functioning and out-patient mental health service use. The study will further investigate the causal ordering of these variables, and thus begin examination of the role of mental health services in preventing subsequent placement change. As such, the study will shed light on processes in two complex service systems designed to provide protective and ameliorative services to vulnerable children and therefore have implications for the delivery of services to children in out-of-home placement. Participants for the study were selected from a cohort of children between the ages of 0-16 who entered foster care in San Diego, California between May 1990 and October 1991 (N=629). The study will use both administrative and mental service use data and will rely on both primary and secondary data collection. Poisson Regression will be used to analyze the relationship as well as the causal ordering of the variables of interest.